Enum regex_syntax::hir::Class

pub enum Class {
    Unicode(ClassUnicode),
    Bytes(ClassBytes),
}

The high-level intermediate representation of a character class.

A character class corresponds to a set of characters. A character is either defined by a Unicode scalar value or a byte. Unicode characters are used by default, while bytes are used when Unicode mode (via the u flag) is disabled.

A character class, regardless of its character type, is represented by a sequence of non-overlapping non-adjacent ranges of characters.

Note that unlike Literal, a Bytes variant may be produced even when it exclusively matches valid UTF-8. This is because a Bytes variant represents an intention by the author of the regular expression to disable Unicode mode, which in turn impacts the semantics of case insensitive matching. For example, (?i)k and (?i-u)k will not match the same set of strings.

Variants

Unicode(ClassUnicode)

A set of characters represented by Unicode scalar values.

Bytes(ClassBytes)

A set of characters represented by arbitrary bytes (one byte per character).

Methods

impl Class

pub fn case_fold_simple(&mut self)

Apply Unicode simple case folding to this character class, in place. The character class will be expanded to include all simple case folded character variants.

If this is a byte oriented character class, then this will be limited to the ASCII ranges A-Z and a-z.

pub fn negate(&mut self)

Negate this character class in place.

After completion, this character class will contain precisely the characters that weren't previously in the class.

pub fn is_always_utf8(&self) -> bool

Returns true if and only if this character class will only ever match valid UTF-8.

A character class can match invalid UTF-8 only when the following conditions are met:

1. The translator was configured to permit generating an expression that can match invalid UTF-8. (By default, this is disabled.)
2. Unicode mode (via the u flag) was disabled either in the concrete syntax or in the parser builder. By default, Unicode mode is enabled.

Trait Implementations

impl Clone for Class

fn clone(&self) -> Class

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Eq for Class

impl PartialEq<Class> for Class

fn eq(&self, other: &Class) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Class) -> bool

This method tests for !=.

impl Debug for Class

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.